class_docstr: Base class for all unsupervised sequence aligners.
class_docstr_tok: ["Base","class","for","all","unsupervised","sequence","aligners","."]
docstr: Fit alignment given series/sequences to align.
  
      core logic
  
  Writes to self:
      Sets fitted model attributes ending in "_".
  
  Parameters
  ----------
  X : list of pd.DataFrame (Series) of length n
      collection of series to align
  Z : pd.DataFrame with n rows, optional
      metadata, i-th row of Z corresponds to i-th element of X
docstr_tok: ["Fit","alignment","given","series\/sequences","to","align",".","core","logic","Writes","to","self",":","Sets","fitted","model","attributes","ending","in","``","_","''",".","Parameters","--","--","--","--","--","X",":","list","of","pd.DataFrame","(","Series",")","of","length","n","collection","of","series","to","align","Z",":","pd.DataFrame","with","n","rows",",","optional","metadata",",","i-th","row","of","Z","corresponds","to","i-th","element","of","X"]
code: def _fit(self, X, Z=None):
      """Fit alignment given series/sequences to align.
  
          core logic
  
      Writes to self:
          Sets fitted model attributes ending in "_".
  
      Parameters
      ----------
      X : list of pd.DataFrame (Series) of length n
          collection of series to align
      Z : pd.DataFrame with n rows, optional
          metadata, i-th row of Z corresponds to i-th element of X
      """
      raise NotImplementedError
  
file_path: sktime/sktime/alignment/base.py
imports: from sktime.alignment.utils.utils_align import convert_align_to_align_loc, reindex_iloc
  from sktime.base import BaseEstimator
  from sktime.datatypes import check_is_scitype, convert
label_desc: Use image node_id 3 for calling the BaseAligner obj's underlying member method code with example usage: obj._fit(X, Z) without return types